Ankle exerciser



FIG. 1 is a bottom perspective view of an ankle exerciser showing our new design;

FIG. 2 is a right side elevation view of the ankle exerciser;

FIG. 3 is a left side elevation view of the ankle exerciser;

FIG. 4 is a front elevation view of the ankie exerciser;

FIG. 5 is back elevation view of the ankie exerciser; and,

FIG. 6 is a top plan view of the ankle exerciser. 

CLAIM The ornamental design for an ankle exerciser, as shown and described. 